NAME

tunnels - Shorewall VPN definition file

SYNOPSIS

/etc/shorewall/tunnels

DESCRIPTION

The tunnels file is used to define rules for encapsulated (usually
encrypted) traffic to pass between the Shorewall system and a remote
gateway. Traffic flowing through the tunnel is handled using the normal
zone/policy/rule mechanism. See
〈http://www.shorewall.net/VPNBasics.html〉 for details.
The columns in the file are as follows.
TYPE —
{ipsec[:{noah|ah}]|ipsecnat|ipip|gre|pptpclient|pptpserver|{openvpn|openvpnclient|openvpnserver}[:{tcp|udp}][:port]|generic:protocol[:port]}
Types are as follows:
ipsec - IPv4 IPSEC
ipsecnat - IPv4 IPSEC with NAT Traversal (UDP port 4500 encapsulation)
ipip - IPv4 encapsulated in IPv4 (Protocol 4)
gre - Generalized Routing Encapsulation (Protocol 47)
pptpclient - PPTP Client runs on the firewall
pptpserver - PPTP Server runs on the firewall
openvpn - OpenVPN in point-to-point mode
openvpnclient - OpenVPN client runs on the firewall
openvpnserver - OpenVPN server runs on the firewall
generic - Other tunnel type
If the type is ipsec, it may be followed by :ah to indicate that
the Authentication Headers protocol (51) is used by the tunnel
(the default is :noah which means that protocol 51 is not used).
NAT traversal is only supported with ESP (protocol 50) so
ipsecnat tunnels don’t allow the ah option (ipsecnat:noah may be
specified but is redundant).
If type is openvpn, openvpnclient or openvpnserver it may
optionally be followed by ":" and tcp or udp to specify the
protocol to be used. If not specified, udp is assumed.
If type is openvpn, openvpnclient or openvpnserver it may
optionally be followed by ":" and the port number used by the
tunnel. if no ":" and port number are included, then the default
port of 1194 will be used. . Where both the protocol and port
are specified, the protocol must be given first (e.g.,
openvpn:tcp:4444).
If type is generic, it must be followed by ":" and a protocol
name (from /etc/protocols) or a protocol number. If the protocol
is tcp or udp (6 or 17), then it may optionally be followed by
":" and a port number.
ZONE - zone
The zone of the physical interface through which tunnel traffic
passes. This is normally your internet zone.
GATEWAY — address-or-range
The IP address of the remote tunnel gateway. If the remote
gateway has no fixed address (Road Warrior) then specify the
gateway as 0.0.0.0/0. May be specified as a network address and
if your kernel and iptables include iprange match support then
IP address ranges are also allowed.
GATEWAYZONES (Optional) — [zone[,zone]...]
If the gateway system specified in the third column is a
standalone host then this column should contain a comma-
separated list of the names of the zones that the host might be
in. This column only applies to IPSEC tunnels where it enables
ISAKMP traffic to flow through the tunnel to the remote gateway.

EXAMPLE

Example 1:
IPSec tunnel.
The remote gateway is 4.33.99.124 and the remote subnet is
192.168.9.0/24. The tunnel does not use the AH protocol
#TYPE ZONE GATEWAY
ipsec:noah net 4.33.99.124
Example 2:
Road Warrior (LapTop that may connect from anywhere) where the
"gw" zone is used to represent the remote LapTop
#TYPE ZONE GATEWAY GATEWAY ZONES
ipsec net 0.0.0.0/0 gw
Example 3:
Host 4.33.99.124 is a standalone system connected via an ipsec
tunnel to the firewall system. The host is in zone gw.
#TYPE ZONE GATEWAY GATEWAY ZONES
ipsec net 4.33.99.124 gw
Example 4:
Road Warriors that may belong to zones vpn1, vpn2 or vpn3. The
FreeS/Wan _updown script will add the host to the appropriate
zone using the shorewalladd command on connect and will remove
the host from the zone at disconnect time.
#TYPE ZONE GATEWAY GATEWAY ZONES
ipsec net 0.0.0.0/0 vpn1,vpn2,vpn3
Example 5:
You run the Linux PPTP client on your firewall and connect to
server 192.0.2.221.
#TYPE ZONE GATEWAY GATEWAY ZONES
pptpclient net 192.0.2.221
Example 6:
You run a PPTP server on your firewall.
#TYPE ZONE GATEWAY GATEWAY ZONES
pptpserver net 0.0.0.0/0
Example 7:
OPENVPN tunnel. The remote gateway is 4.33.99.124 and openvpn
uses port 7777.
#TYPE ZONE GATEWAY GATEWAY ZONES
openvpn:7777 net 4.33.99.124
Example 8:
You have a tunnel that is not one of the supported types. Your
tunnel uses UDP port 4444. The other end of the tunnel is
4.3.99.124.
#TYPE ZONE GATEWAY GATEWAY ZONES
generic:udp:4444 net 4.3.99.124